I don't think my girlfriend wants to go to homecoming with me?

So I asked my __ if she usually is asked rather than be asked to dances and she said “asked, why?” And I said, “just wondering” because I was thinking when the time comes, I'd ask her, but the problem is that we are a secret couple because both of our parents don't know that we are bisexual and they wouldn't accept us if they found out. And we can't tell people because obviously it will find its way to our parents.

Sooo, she said. “Idk because my friend group might ditch me because they have dates or whatever”

So I say, “I'm sure someone will ask you. I know I want to invite someone special” and I've said this a couple times before. But after I said that, she usually doesn't say anything flirty back, she just is quiet for awhile. Maybe the fact that if we go together, our parents will find out or it won't work out because people can't find out we are dating? But we could always tell people we are going as friends...

Ideas? And how I can confront her to ask her if she just doesn't want to go with me or is worried?